Driving burden estimation device and driving burden estimation method

A driving burden estimation device, which is equipped to a subject vehicle and estimates a driving burden on a driver of the subject vehicle, includes a distance detection portion detecting an inter-vehicle distance between a non-subject vehicle travelling ahead of the subject vehicle and the subject vehicle, a speed detection portion detecting a traveling speed of the subject vehicle, a calculation portion calculating an inter-vehicle time taken until the subject vehicle reaches a present location of the non-subject vehicle based on the inter-vehicle distance and the traveling speed, and a burden estimation portion estimating the driving burden according to the inter-vehicle time and the traveling speed in such a manner that the driving burden decreases as the traveling speed becomes higher under a same inter-vehicle time.